Hot answers tagged

90

Technically, yes, it would be easier to put people on Venus. You need less of a kick for the interplanetary trip and slowing down is trivial with that dense atmosphere...one of the Pioneer Multiprobe sub-probes made a soft landing despite only being designed as atmospheric probes. However, the surface temperature stays close to 464 °C, with over 90 ...


48

As others have already pointed out, getting humans to Venus would be marginally easier than getting them to Mars. Let's consider survival on Venus in a little more detail though. Although there haven't been any manned missions to either Mars or Venus, there have been unmanned missions to both. So let's consider how long those unmanned missions have survived. ...


48

The teeth served an aerodynamic function. ...metal teeth were added to the periphery of the impact ring in an effort to reduce the spin and oscillation during the descent and prevent the rough landings experienced by the 1978 missions. This is also why the earlier missions didn't have them, they were added in an attempt to mitigate problems experienced on ...


35

The Venus flyby does indeed make the mission shorter, but it has some pretty serious negative consequences as well. The mission spends much more time in deep space. Approaching the sun will increase the amount of radiation exposure by a large amount. The thermal design would need to be rethought to survive that close to the Sun. The time on Mars for a Venus ...


32

Can't speak to the trajectory aspects but the Orbiter crew compartment was very intolerant of crush pressure loading. The two negative pressure relief valves protect the crew compartment from being crushed if ambient pressure rises above the pressure in the cabin. These negative pressure relief valves will crack when ambient pressure is 0.2 psid greater ...


30

Is such an orbit even possible? TL;DR: If the Sun wasn't around, yes, such an orbit is possible. But since the Sun is around, such an orbit is impossible. About the name of the orbit Quoting from Emily Lakdawalla, who has a bit more gravitas than some random file blogger, What is a geostationary orbit like at Mars? I have to pause here for a brief ...


25

The Soviet Union actually deployed balloons on Venus, so I assume they studied them before that. https://en.wikipedia.org/wiki/Vega_program#Balloon


20

It's the third in a series. Planet-A, "Suiseu" studied Halley's comet. Planet-B, "Nozomi" visited Mars. Looks like there's a Planet-D (PDF link) planned for visiting Venus, too.


17

The same WP article on Venus in fiction referenced by the OP documents one specific scientist who believed, in a nonfiction sense, that Venus is indeed the world envisioned by mid-20th-Century writers: In 1918, chemist and Nobel Prize winner Svante Arrhenius, deciding that Venus's cloud cover was necessarily water, decreed in The Destinies of the Stars that ...


17

What does the discovery of phosphine mean for the future of Venusian exploration? It certainly adds some impetus. However, The discovery has not yet been independently confirmed. This alone is very important. What if the discovery was not a discovery at all? If confirmed, devising a measuring device that can withstand the extremely acidic nature of the ...


15

Was there any proposal or study for a balloon in the Venus atmosphere? Yes and kudos to OrganicMarble's power of deductive reasoning! I am sure there have been several proposals or studies of this. Below is a 2018 report of a meeting of over 50 expert participants and it likely contains a thorough listing and summary of previous studies as well as current ...


15

Let's talk about the major materials that made up the Venera landers. https://space.stackexchange.com/a/9965/25 has a great summary of what the landers were made of, they are composed of include Titanium, gold, fiberglass, KG-25 an high-temperature polyurethane foam, and PTKV-260. There are a bunch of other materials, likely including some glass and other ...


15

Due to thermodynamics, the temperature must increase. Heat flows from hot to cold, and can not go the other direction. If there is a cold pocket between the (hot) core and the (hot) atmosphere of Venus, heat will flow into it. For it to remain cold, this heat would have to be dumped elsewhere, but since there's no colder place nearby for it to leak heat, it ...


13

From the recently published paper Phosphine gas in the cloud decks of Venus. The presence of PH3 implies an atmospheric, surface or subsurface source of phosphorus, or delivery from interplanetary space. The only measured values of atmospheric phosphorus on Venus come from Vega descent probes, which were only sensitive to phosphorus as an element, so its ...


12

Is it possible to create a cycler that can travel from Venus to Mars, then back to Venus? Yes. When only two planets are involved, there are several infinite families of cycler orbits. Given the 434 day long orbital period of an ellipse touching both Venus and Mars is almost twice as long as the 225 days orbital period of Venus, it's even possible to ...


12

First of all, rocks from Earth are probably just about everywhere in the Solar System. One simple example is this rock found on the Moon. A number of pieces of Mars have been found on Earth, and if that has happened, no doubt there are Earth rocks on Mars. If Earth life can survive a vacuum it has probably gotten to everywhere in the Solar System anyways. ...


12

What makes this somewhat different form the case of Mars is that the orbit of Venus is pretty round. It has even less eccentricity than the orbit of the Earth. Therefore, all "good" close approaches are going to happen close to the perihelion of the Earth. As a first order approximation, that means "good" encounters are somewhere in the ...


11

The atmospheric pressure of Venus would crush any human. Mars would therefore be a slight more hospitable. It may be red and dry, but it doesn't rain acid!


10

In very rough terms, based on data from Wikipedia and NASA sites An empty SpaceShuttle is around 165 000 pounds, and has volume roughly Height, 56.1 m (184 ft 1 in). Diameter, 8.7 m (28 ft 7 in). So, a density of about 22.5 kg/m^3, while Venus' atmosphere at ground level is 67 kg/m^3, so the Shuttle would float 'way up there somewhere around 15 km ...


10

An ISAS mission in development is known by a series and a letter. After successful launch, it gets a name, based on suggestions from its developers. One I worked on, ASTRO-E, unsuccessfully launched, was rebuilt as ASTRO-E2. Once successfully launched, it was named "Suzaku", after a mythical bird that is reborn in some stories.


9

There's a lot in here, but let me get the major things. Landing on Venus is pretty much impossible for humans with current technology. Mars is much easier, we can do that, Venus would be extraordinarily difficult, to say the least. There are at least 4 missions with some US backing that are proposed and under active funding. Rocket Lab's private Venus ...


8

That's what I found so far. In Abdrahimov, Basilevsky [2002] Venera photos are used for geological context interpretation comparing with orbital radar data. quotes: The photogeologic analysis shows that the material of plains with wrinkle ridges (Pwr) dominates the Venera-9 landing-site ellipse (it occupies ~60% of the area of the ellipse). The material of ...


8

There are easier ways to enhance Mars's atmospheric pressure, so no, don't use Venus materials. I calculated the energy required to lift a kg of nitrogen — or a kg of anything, for that matter — out of Venus's gravity well, and uphill through the sun's gravity well to Mars. Getting it away from Venus was a small part of the total, but that total was nearly ...


8

While Mars is more expensive to reach than Venus (it requires more delta-v, thus your payload-to-fuel ratio is smaller on a Mars mission than a Venus mission, everything else being the same), we have all of the technologies needed to put humans on Mars and sustain them for a substantial period of time. Sure, we have to build the spaceships and refine some ...


8

While the earth's magnetic field was disturbed by the tests mentioned, I don't think there's any sign that the field as a whole was degraded, certainly not on a timescale that would materially affect atmospheric escape. Venus already has no intrinsic magnetic field to be disrupted. The existing field is induced by the sun's effect on the planet. If it were ...


6

Apparently you can't see very far, but not because of mist. The visibility was a pleasant surprise to the scientists who, after reviewing Venera 8, had predicted a dark, murky and dusty atmosphere in which only the near field would be available for inspection. The indistinctness and apparent nearness of the horizon in all of the images from the Venera ...


6

In addition to the problems already mentioned, Venus rarely passes between the Earth and the Sun, and when it does, it only lasts for a few hours: https://en.wikipedia.org/wiki/Transit_of_Venus. That link also contains a good image that shows the difference in size between Venus and the Sun: the former is a tiny black dot compared to the latter. Any cooling ...


6

No. Moving N2 or O2 wouldn't make sense, because it would require moving about a quadrillion tons from one planet to another, while we've barely figured out how to move one ton up from one gravity well and down into another. Once we can do that kind of engineering (pick a favorite technology from science fiction), we may have already become bored with ...


6

The geothermal gradient on Venus may be no higher than 14K/km, that it get's warmer (not cooler) with increasing crustal depth. Locally crustal units are not closed systems but in exchange with adjacent parts, heat from below and atmosphere from above, so the gradient may be 0 or even negative, for instance when fluids take heat away or in subduction zones (...


5

Yes. Here's a recent proposal, Calypso, which involves a balloon in the high atmosphere lowering a probe beneath the cloud layer. The probe would be drawn up to cool off when it starts to overheat: https://www.space.com/venus-calypso-surface-survey-idea.html


Only top voted, non community-wiki answers of a minimum length are eligible